To answer that question first we should consider the different operational designs that are available for lift tables. Lift tables are most commonly available in hydraulic, pneumatic, and self-leveling operations.
Pneumatic lift tables are acceptable or required in certain applications in which electrical and hydraulic components are not desired or allowed. They are not as precise in positioning as hydraulic. The sizing availability is limited as well. They are typically limited to 24” of vertical travel.  https://www.pentalift.com/lift-tables/prodinfo-pro-air-lift.php
Self levelling lift tables are used in a palletizing or de-palletizing application therefore based on typical pallet weights and pallet sizes they are designed to meet the capacity and pallet size accordingly. They utilize stored spring energy to position the load in a general location that is not precise or exact. The sizing availability is limited as well. https://www.pentalift.com/lift-tables/prodinfo-self-leveling.php
Hydraulic lift tables offer the widest range of performance and safety features available. From 40’ of vertical travel https://www.pentalift.com/lift-tables/customprodinfo-dual-quad-scissor-lift.php lifting capacities from 500 lb. to 120,000 lb. https://www.pentalift.com/lift-tables/customprodinfo-pentaflow-hyd-cylinder.php and hydraulic lift tables/tilters are also the most commonly used ergonomic work positioner. https://www.pentalift.com/lift-tables/lift-tables.php
In summary hydraulic lift tables are the most common operating system because they are available in the widest range of designs with the highest range of capacities to suit almost any lift and positioning application. For additional information on Pentalift lift tables and positioning equipment please contact the Pentalift Sales Department